1. Field of the Invention
The present invention generally relates to a resistive memory apparatus and a write-in method thereof, and more particularly, to a cross-bar resistive memory apparatus and write-in method thereof.
2. Description of Related Art
Based on the demand for next-generation non-volatile memory, a kind of resistive memory have been developed. This resistive random memory access can be random accessed, and be used to replace the NAND flash memory. In order to increase the density of memory, a high-density three-dimensional vertically arranged resistive memory apparatus is also been proposed.
In a cross-bar resistive memory apparatus, the most concerned issue is that, as performing a data-writing operation on the memory cells of the cross-bar resistive memory apparatus, the unselected memory cells arranged in the same memory columns and the same memory rows as ones of the selected memory cells would produce voltage differences due to the voltages delivered on the bit-lines and the word-lines, which causes the resistance thereof adjusted into a region to be reset and triggers data-storing error.
The aforementioned situation becomes particularly serious for the resistive memory apparatus with asymmetric memory characteristic. In such a resistive memory apparatus, the relation between current and voltage in the resetting state of the memory cell is asymmetric with the relation between current and voltage in the setting state of the memory cell thereof. Thus, any solution in the prior art to reset and set the resistive memory cells with asymmetric characteristic by using a same voltage is apparently not appropriate.